This invention relates to a medical device and to an associated medical technique. More particularly, this invention relates to an endoscopic sheath assembly and to an associated endoscopic method.
Flexible endoscopes are inserted into the digestive tract for diagnostic and therapeutic purposes. Endoscopes generally include a light guide for transmitting optical-wavelength electromagnetic radiation into the patient. Images are captured, typically via lenses and an optical fiber bundle or a charge-coupled device, whereby a user can visually inspect the inner walls or surfaces of the digestive tract. One common objective of endoscopic investigations in the digestive tract is to detect the presence of polyps. Where a polyp is visually detected, particularly in the colon, it should be severed, captured, and removed from the patient. Alternatively, particularly where the polyp may be a malignant cancer, the polyp may be severed and captured for extraction from the patient.
One problem in endoscopy is the potential for the transmission of infection from one patient to another because of remaining bioburden inside or on the endoscope. Traditionally, this problem is countered by thoroughly cleaning the instrument. However, it is difficult to adequately clean an endoscope, particularly the biopsy channel thereof. One solution has been to encase the endoscope insertion member in a disposable sheath which is sealed to prevent the accumulation of bioburden inside or on the endoscope. Such a sheath is made of a very delicate thin material and is long, flimsy and very narrow. To securely apply the sheath to an endoscope without ripping the sheath is difficult. Removing a sheath from an endoscope without contaminating the endoscope is also difficult.